MIC4685

Micrel

September 2002

3

MIC4685

Electrical Characteristics

V

Parameter

Condition

Min

Typ

Max

Units

Feedback Voltage

(

±2%)

1.210

1.235

1.260

V

(

±3%)

1.198

1.272

V

8V

≤ V

1.186

1.235

1.284

V

1.173

1.297

V

Feedback Bias Current

50

nA

Maximum Duty Cycle

V

94

%

Output Leakage Current

V

5

500

µA

V

1.4

20

mA

Quiescent Current

V

6

12

mA

Bootstrap Drive Current

V

250

380

mA

Bootstrap Voltage

I

5.5

6.2

V

Frequency Fold Back

V

30

70

120

kHz

Oscillator Frequency

180

200

225

kHz

Saturation Voltage

I

0.59

V

Short Circuit Current Limit

V

3.5

6

A

Shutdown Current

V

150

200

µA

Enable Input Logic Level

regulator on

2

V

regulator off

0.8

V

Enable Pin Input Current

V

16

50

µA

V

–1

–0.83

mA

Thermal Shutdown @ T

J

160

°C

Note 1.

Exceeding the absolute maximum rating may damage the device.

Note 2.

The device is not guaranteed to function outside its operating rating.

Note 3.

Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k

Ω in series with 100pF.

Note 4.

2.5V of headroom is required between V

3.3V circuit on page 1.

Supply Voltage (V

Enable Voltage (V

Steady-State Output Switch Voltage (V

Feedback Voltage (V

Storage Temperature (T

ESD Rating Note 3 ....................................................... 2kV

Supply Voltage (V

Junction Temperature (T

Package Thermal Resistance

θ

θ